Where do you guys get your fans?

[NoctisReitop]

Yeah. There's an intake in the front. It's a 120mm. It doesn't move much air though; probably 20 cfm at best (I can't find any info on it, but if I dangle a streamer near it, it barely moves it).
I also have a "bottom" intake. It's a 92mm fan mounted in the back that ducts air from the back, up through the bottom middle. I figured that it'd help with whatever obstruction the GeminII would create. You can see it in the picture I posted. It's the silver looking tube coming up from the bottom. That particular fan is ducting 36 cfm up through the bottom.
These are the only two other fans that push air in/out of the case. The other four are mentioned previously (excluding the fans on the GeminII): 2 top, 2 rear.
I'm not sure what my montage of fans is doing for my circulation. The GeminII looks like it's obstructing whatever is being done by the 4 fans in the upper rear of my computer. I haven't even put a lot of thought into the pressure.

[polobunny]

Originally Posted by yellowhello

Well, the reason I say that more exhaust is better is because then there is negative pressure in the case. That way, the air is sucked through the heatsinks rather than around them. The only reason positive pressure is good (more intakes than exhaust) is because that way less dust gets into the case.

Your post is "half true". Positive pressure will indeed bring less dust in your computer, but it will also reduce noise (albeit not a lot, depending on your configuration) compared to a negative pressure environnement.

As for sucking air trough heatsinks, this makes no sense at all. Whether your pressure is negative or positive inside your case, air will go through your heatsink. It makes no sense to assume that your CPU heatsink for one, will suck the air faster or such through the fins because the air pressure in the case is negative (lower pressure inside the case than outside) as the CPU is taking air from inside the case and blowing that same air... still inside the case. There's no pressure change there. ;) There's only 1 setup where this would be true and it's if the CPU heatsink + fan was pushing air almost directly out of the case.
However, if you take it to the extreme, a negative pressure will leave the ambiant temperature in your case lower (therefore maybe affect your CPU temps doing so) yet make more noise and bring more dust through cracks between your CD-rom covers and such.

What really matters in the end is how much air you push in and suck out.

Ideally, I want a neutral pressure in my case. This is a great balance between cooling performance, dust accumulation and noise. In the case I want an extremely cool system at all price, i'd go for a negative pressure. In a dusty environnement, i'd sacrifice temps a bit to keep the dust out by having a positive pressure and putting filters on the intake fans.

And Noctis, sorry to bother you with all this technicalities, but is it possible for you to submit pictures of your whole setup with CFM ratings for your fans? This way someone can give their advice on fans and try to leave you with a decent fan setup. :)

[Yellowhello]

Well polo, I'll take your word for it... I'm no expert but I do remember distinctly hearing that a negative pressure is better... well, I guess I learned something.:dontknow:

[NoctisReitop]

Sure. Short form:
Rear: 2x 92mm intake. 2100 rpm, 23 dba. \
Top: 2x 120mm exhaust. 1200 rpm, 21 dba. > No idea on cfm rating
Front: 1x 120mm intake. 1200 RPM, 21dBA /
Bottom: 1x 92mm intake. 2100 rpm, 26 dBA, 36.89 CFM

(other fans that don't really make a difference)
2x 120mm Arctic 12 fans for GeminII
2x 120mm HDD intake fans, 1200rpm, 21dBA (simply pull air in one side and out the other. Being it's a hdd channel, per se, it doesn't appear to me to affect the air in the case at all)





Links:
Case fans (rear, top, and hdd)
Bottom fan
Front fan

[RangerXLT8]

I just thought I'd drop in and clue you into a very good place for fans. It's Welcome to Sidewinder Computers - Your Supplier of High Quality PC Modding and Cooling parts and they have, ALL Panaflo, Delta, Thermaltake, Antec etc in all different sizes. They also will sleeve the wires and will customize connectors. It's a really great company.

One year I ordered so much from them they sent me a handwritten and signed Christmas card. Their shipping is fast, they use Priority mail.

[RangerXLT8]

Originally Posted by NoctisReitop

Sure. Short form:
Rear: 2x 92mm intake. 2100 rpm, 23 dba.
Top: 2x 120mm exhaust. 1200 rpm, 21 dba. > No idea on cfm rating
Front: 1x 120mm intake. 1200 RPM, 21dBA /
Bottom: 1x 92mm intake. 2100 rpm, 26 dBA, 36.89 CFM

(other fans that don't really make a difference)
2x 120mm Arctic 12 fans for GeminII
2x 120mm HDD intake fans, 1200rpm, 21dBA (simply pull air in one side and out the other. Being it's a hdd channel, per se, it doesn't appear to me to affect the air in the case at all)





Links:
Case fans (rear, top, and hdd)
Bottom fan
Front fan

That airflow layout makes so sense to me and is backwards in my mind. Except forthe mid front intake fan. Exhaust goes out the back, heat rises so use those rear and top fans for exhaust, and everything else for intake...

[polobunny]

Originally Posted by yellowhello

Well polo, I'll take your word for it... I'm no expert but I do remember distinctly hearing that a negative pressure is better... well, I guess I learned something.:dontknow:

You don't have to take my words for it. I'm sure you can find tons of information on the matter. ;)
And while this was an example with a computer case, those are physics. It applies to anything else on our superb blue planet.

Edit: Noctis, your power supply is at the bottom in a "up" position? If so, it makes no sense to draw air from the bottom low fan, you're only going to suck your hot power supply air back in your system. :/
Same applies for the 2 92mm at the top back. They're just gonna suck hot air back in from your video card (which seems to throw hot air out). :S
I think those 2 fans are likely not doing very much more than noise, as hot air is already sucked out from your system by those 2 120mm at the top. Even more since the top 92mm is throwing it's air right into the first 120mm.

The 2 120mm for the HDD's don't look like they would change your ambiant temperature much. You might want to quiet them though, for the sake of it. Take similar fans but with a lower noise (you can find good 10-12 dBA fans that probably do the same if not a better job.

Lemme think about something a bit more efficient than that, which is currently only spinning hot air around. I'll get back to you ASAP. =]

[NoctisReitop]

No, the power supply is standing on its side. The fan pulls room air from the side (there's a screen there) and exhausts out the back. But I guess that does inspire some re-circulation of exhaust =\.

As for the recommendation of noise, all the fans with the exception of the one I bought separately (goes with the mod at the bottom rear, 36 cfm) are as good as silent.

[Yellowhello]

Noctis, just turn the two 92mm fans around so they are exhausting air and that is a pretty good short term solution. After that, I'd be looking at some new fans, and there have been plenty recommended previously.

[polobunny]

Originally Posted by yellowhello

Noctis, just turn the two 92mm fans around so they are exhausting air and that is a pretty good short term solution. After that, I'd be looking at some new fans, and there have been plenty recommended previously.

That does seem like the simple answer, but he's getting a damned negative pressure environnement doing so.
And that's what I meant Noctis, just couldn't find exactly how to word it, I was in a rush. :P